Search

This paper offers an electromagnetism-like (IEM) algorithm to estimate the five parameters of a single-diode PV module’s model. IEM uses local search and improves movement step to increase the convergence to optimal solutions. The key of improvement is performed by adding a nonlinear equation to adjust the length of the particle in each iteration. Moreover, the total force formula is simplified to speed up the exploration for an optimal solution. Analyses are carried out by experimental data points at various operational conditions to show the stability and reliability of the proposed methods. The results of the proposed IEM algorithm show a better convergence speed and high accuracy compared with other models in the literature, which involves various statistical errors. The values of average root mean square error, mean bias error, standard deviation, average absolute error, and average test statistic of the proposed method are 589%, 0.51%, 0.19%, 46%, and 0.53, respectively. As a conclusion, the IEM algorithm presents better performance than other methods in the literature in terms of accuracy and convergence.

A Hybrid Energy System (HES) is a mechanism that combines multiple sources of energy connected together to achieve synchronised energy output. However, increased energy consumption, operator energy expenses, and the potential environmental impact of increased emissions from the exhaustion of non-renewable energy resources (fossil fuel) pose major challenges to HES. This research is to conduct energy management strategy based on a demand response (DR) program and a hydrogen storage system by designing a Program Logic Controller (PLC) unit. The hybrid system is evaluated by comparing different scenarios such as a hydrogen energy system and demand response. The purpose of this research is to reducing peak demand, minimise the cost of the system and also to extract surplus power generation out of the rate of the battery. This can be achieved by improving the system performances and by eliminating any degradation at the early stages. Organisations or companies must be sure their systems are working properly and that their investments will pay off.

Individual remote agro-based micro-grid is prone to reliability and resilient instability issues due to large sudden load or generation fluctuations. Therefore, it is important to integrate several micro-grids to solve the issue of reliability. An interconnected micro-grid system takes advantage of various complementary energy sources and effectively coordinates the energy sharing among the neighbouring micro-grids to improve the stability, reliability, and energy efficiency of the system in case of loss or insufficient power supply from one micro-grid. Control of energy management and communication for inter-micro-grid becomes complex and challenging in these areas due to the excess demand of agro-based consumer loads. In this paper, a decision-making algorithm that provides smart solution in interconnecting several neighbouring micro-grids to optimally share the supply is developed. A case study is presented and HOMER Pro software is used to optimize three proposed micro-grids and ensure optimal energy sharing.

Lightning Induced Overvoltages (LIOVs) on short, floating Medium Voltage (MV) lines can be either calculated or measured using existing methods. These results are then normalized and extrapolated to estimate the lightning performance of long operational MV lines. Existing models can become complicated and some crucial input data may not be available when the line is long, has line equipment connected to it and is energized. Accurate LIOV measurements on an operational MV line are not viable due to the large number of measurement instruments required and the accompanied logistics. This paper describes a new measurement method to distinguish between nearby lightning and direct lightning strikes to the line for lightning performance investigations. It also indicates whether the LIOV exceeded the line Basic Insulation Level (BIL).

Micro-grids implemented in remote areas are faced with the uncertainty between variable supply resources and load demands. This gap is a major issue in agricultural-based remote landscapes due to the additional irrigation load demand. The available Hybrid micro-grid system models are not optimized with respect to sizing and costing to meet reliably and cost effectively the load demand of an agro-based off-grid remote communities. Therefore, a techno-economic feasibility study has been undertaken to investigate the prospects of renewable energy-based off-grid Hybrid micro-grid to support rural electrification to power residential loads and irrigation system loads. In this paper, a Solar PV, Wind and Battery storage Hybrid system is optimized with respect to sizing and costing using HOMER Pro software to meet the demand of an agro-based off-grid rural landscape, reliably and cost effectively.

A new system of processing galena concentrates has been developed using the non-blast method of lead reduction from its sulphides by metallic iron. Excavated slag was used as flux agents to generate the stackable sulfur-containing products, instead of sulfuric acid. Based on this relatively modern technical concept of extreme energy saving, the new system of concentrate processing has been developed. The system includes an iron reduction and zinc sublimation system from excavated slag by soot-hydrogenic mixture, products of pyrolysis of natural gases, lead ousting in crude metal from its sulphides by metallic iron in the autogenous conditions of the rotary mixer, regenerative utilization of thermic wastes of the system, and neutralization of SO2 gases by reagents obtained aboard (ZnO, Fe). The new system will reduce the effective specific equivalent fuel consumption by a factor of 3.77, and it will also expand the utilization factor of material waste products by a factor of 2.5-3 in comparison with the traditional methods of concentrate processing.

This paper presents the design, simulation and analysis of the distribution of lightning current and transient voltage in a 25 kV AC railway traction system. Consequently, the lightning protection system that may mitigate the adverse effects due to possible lightning strikes has been designed. The Mpumalanga- Richards Bay Coal line in South Africa has been considered for the analysis. The railway system is modelled, consisting of a mast, an insulator applying a back flashover control mechanism, overhead catenary wires, a pantograph, an AC locomotive and the rails. The main component of protection is the surge arrester that is designed using the PincetiGiannetoni model. The surge arrester is rated at 30 kV, with a nominal discharge current of 10 kA. The complete system is modelled and simulated in PSCAD software. The simulations are performed to detect the transient response of critical components of the system when lightning current is injected at locations of exposure, namely; the mast, catenary wires and the pantograph, in the absence and presence of surge arresters. The results show a significant decrease in the peak current and voltage of the selected components when surge arresters are connected.

Despite the significantly large number of deaths and injuries, the property loses and service downtime, lightning is not treated as a serious natural hazard in many countries of which lightning ground flash density is notably high. In this chapter, we highlight this lack of attention from both government and non-governmental sectors as a substantial barrier to curb lightning related losses. The ignorance of experts and statutory bodies that control the implementation of standards and guidelines have paved the way to the flooding of fraudulent products and technologies into the respective countries. The attitudinal issues and negligence of responsibilities of engineering and managerial capacities of both private and government sectors contributes to the mishaps and losses due to lightning-related incidents. The chapter finally discusses possible mechanisms of promoting lightning protection as business ventures in less-privileged communities by developing entrepreneurship among people having low to medium levels of technical know-how.

Being a spectacular atmospheric phenomenon, lightning could induce significant interest in the human mind since the beginning of history. Most often the public perceptions of many communities about lightning were marked by divinity, power, fear and punishment. The belief systems extend up to the present time, despite the development of modern science and technology. In the last two centuries, the scientific understanding of the thunderstorm and lightning phenomena gradually improved and at present we have a significant awareness of the nature of lightning, injury mechanisms and lightning-related medicine. The modern safety guidelines and safety modules for communities in lightning-dense geographical areas are based on proven scientific facts. In several developed countries, a marked decrease in the number of lightning casualties could be observed during the past century, due to the continuous safety awareness programs. However, lightning safety modules which are highly successful in one part of the world may not be that successful in another part of the world.

Solar energy is considered one of the most important renewable energy resources, and can be used to power a stand-alone photovoltaic (SAPV) system for supplying electricity in a remote area. However, inconstancy and unpredictable amounts of solar radiation are considered major obstacles in designing SAPV systems. Therefore, an accurate sizing method is necessary to apply in order to find an optimal configuration and fulfil the required load demand. In this study, a novel hybrid sizing approach was developed on the basis of techno-economic objectives to optimally size the SAPV system. The proposed hybrid method consisted of an intuitive method to estimate initial numbers of PV modules and storage battery, an iterative approach to accurately generate a set of wide ranges of optimal configurations, and a Pareto envelope-based selection algorithm (PESA-II) to reduce large configuration by efficacy obtaining a set of Pareto front (PF) solutions. Subsequently, the optimal configurations were ranked by using an integrated analytic hierarchy process (AHP) and vlsekeriterijumskaoptimizacija i kompromisonoresenje (VIKOR). The techno-economic objectives were loss of load probability, life cycle cost, and levelized cost of energy. The performance analysis results demonstrated that the lead&ndash, acid battery was reliable and more cost-effective than the other types of storage battery.

Songo rectifier station is located 6 km away from the Cahora Bassa (CB) hydroelectric power station. It was designed to transmit 1920 MW from the 2075 MW generated to the Apollo inverter station in South Africa. Frequency fluctuation at Songo is very high because the active power balance is easily destroyed after an HVDC disturbance. Faults on the three HVAC transmission lines, faults on the two HVDC transmission lines and trips of the converter bridges make Songo rectifier station Busbar I (BBI) susceptible to overfrequencies. Load rejections can be large because the generators and converter bridges operate most of the time under full load conditions. Frequency fluctuation has a negative impact on the interconnected system. It causes the tripping of the sharply tuned AC harmonic filters and consequent tripping of the HVAC bus coupler (BC) at Songo, resulting in power reduction to Eskom or to ZESA. It may also cause the tripping of the converter valve cooling pumps due to overload and consequent tripping of the entire HVDC station. To propose mitigating measures to the overfrequencies occurring at Songo BBI, the actual behaviour of the Grid Master Power Controller (GMPC) and the actual behaviour of the HVDC scheme controls were analyzed through data recorded in the last 10 years by the Transient Fault Recorder (TFR) installed at Songo. The results reveal that frequency deviations have increased in recent years at the rectifier station mainly due to the failure of the inverter station to take over current control after HVDC disturbances. This increases the magnitude of the load rejections.

Weather risk perception research lacks multihazard and transcultural datasets. This hypothesis-generating study used a cognitive behavioral approach and Brunswik’s lens model for subjective risk parameters across eight countries. In Germany, Poland, Israel, the United States, Brazil, India, Malaysia, and Australia, 812 field interviews took place with a uniform set of 37 questions about weather interest, media access, elementary meteorological knowledge, weather fear, preparedness, loss due to weather, and sociodemography. The local randomized quota samples were strictly tested for sample errors; however, they cannot be considered representative for individual countries due to sample size and methodology. Highly rated subjective risks included flood, heat, tornado, and lightning. Weather fear was most prominent in the Malaysian sample and lowest in the German. Subjective elements were further explored with bivariate correlations and a multivariate regression analysis. Sociodemography correlated with psychological variables like knowledge, interest, and fear. Fear was related with subjective risk; less educated and informed people were more fearful. A linear regression analysis identified interest, gender, housing type, education, loss due to weather, and local weather access as the significant predictors for preparedness. The level of preparedness was highest in the United States and Australia and lowest in the Malaysian and Brazilian samples. A lack of meteorological training and infrequent loss experiences make media communication important and emphasize the value of repetition for basic information. Elements of this survey can serve to monitor weather-related psychological orientations of vulnerable population groups. Finally, this survey provides a template with which larger representative transcultural multihazard perception studies can be pursued.

Display Omitted Determine the best trading off values between in-house manufacturing and outsourcing in a restricted capacity cellular manufacturing system.A multi-layer perceptron is used for scheduling dynamic cellular manufacturing systems in the presence of cost uncertainty.Propose a new method for measuring the cell-load variation in cellular manufacturing systems.Develop a new method for minimizing system imbalance in dynamic cellular manufacturing systems.It is proved that the inflation rate can increase the system imbalance in dynamic cellular manufacturing systems. In this paper, a new method is proposed for short-term period scheduling of dynamic cellular manufacturing systems in the presence of bottleneck and parallel machines. The aim of this method is to find best production strategy of in-house manufacturing and outsourcing in small and medium scale cellular manufacturing companies. For this purpose, a multi-period scheduling model has been proposed which is flexible enough to be used in real industries. To solve the proposed problem, a number of metaheuristics are developed including Branch and Bound; Simulated Annealing algorithms; Fuzzy Art Control; Ant Colony Optimization and a hybrid Multi-layer Perceptron and Simulated Annealing algorithms. Our findings indicate that the uncertain condition of system costs affects the routing of product parts and may induce machine-load variations that yield to cell-load diversity. The results showed that the proposed method can significantly reduce cell load variation while finding the best trading off values between in-house manufacturing and outsourcing.

Since the beginning of twenty-first century, Malaysian civil and defense systems became increasingly dependent on sophisticated electronic and wireless systems. This led to the use of many intelligent applications and emerging the smart cities which highly rely on modern technologies such as smart telecommunication, smart grid, smart transportation, artificial intelligence, smart health, enterprise Internet of Things, smart building management systems and smart governance. These introduced new services and practices which highly impacting the planning, policy, development, and operation of infrastructure of society, while co-exist with urban facilities, and must be electromagnetic compatible with the existing systems. Hence, it initiated Intentional Electromagnetic Interference which could be a significant threat towards civil, defense, industrial, and commercial sectors, with possible targets of radio and television, telecommunication networks, grid power networks, railway networks, air traffic control, government and banking administrative networks, or even defense system as well. The susceptibility and vulnerability of these sensitive systems due to the electromagnetic interference in the current decades will keep of increasing due to the expansion and spread of radiation sources.. Threats from high power microwave sources and high power electromagnetic pulses and high-altitude electromagnetic pulse on civil and defense infrastructure that include an electronic equipment and wireless systems could be harmful and may cause disturbances and damages on electronic devices and wireless systems. This paper presents an overview of the important events in history related to the high power electromagnetic sources that is paving the way for enhancing the understanding of electromagnetic interference capabilities in disturbing modern infrastructure systems. Several major incidents reported in the literature, which are suspected to have been caused by electromagnetic interference, were also analyzed.

Switching transients generated by a five-step 50 KVAR shunt capacitor bank in a 415 V/240V power system have been characterized with the view of providing a database to investigate their effects on electrical network components. Three balanced single-phase RL loads were connected to the three-phases separately. The results show that the current impulses generated during the switching operations may be high enough to either damage or degrade the equipment connected to the power system. The experimental set up was consequently simulated by means of Power System Computer-Aided Design (PSCAD) software. Data analysis were conducted on the amplitude, the rise time and the pulse duration of the transient current waveform. The results of the experimental Work and the simulation have reasonable agreement. Thus, the PSCAD simulation model could be used to generate capacitor bank switching impulses for various configurations in a low voltage system, to develop a data bank. The measured and simulated transient waveforms are compared with extreme case (higher 5%) of positive lightning waveforms. The outcome of this study can serve as a guide for manufacturing technologists as well as electrical engineers in addressing a main issue of capacitor banks, the generation of switching transients in LV systems and their effects on downstream equipment.

To ensure safety against lightning of wind turbines, high-voltage strike attachment tests specified in IEC 61400-24 are adopted to determine points of lightning attachments. These tests are usually conducted with a small blade sample as a representative of the full-scale blade length. However, incidents of lightning damage to wind turbines are still high, which indicates that small blade samples may not be an adequate representation of full-scale blade. In this paper, the extended vertical tri-pole cloud charge distribution model is used to compare the maximum electric field strength around a full-scale blade and that of a small blade section to show how they affect the maximum electric field strength required for the initiation of upward leaders from wind turbines. The results show an average difference of 15.16% between the maximum electric field relevant to the full-scale blade and that of the blade segment. Thus, a tolerance of 16.95 kV/m is recommended in using the blade segment in the laboratory testing. The results of the point of initiation of upward leader coincides with experimental data from lightning discharge attachments.

Standalone photovoltaic (SAPV) systems have been considered as promising and fast development renewable energy sources due to free-noise, easy availability, and low-cost, especially for remote areas. However, the main disadvantages of these systems are low energy conversion and high capital cost. Therefore, many factors should be considered before installing the SAPV systems such as types of PV panels and configurations, mathematical models of PV module, storage battery, environmental criteria, sizing method based on techno-economic objectives, and selection the final optimum configuration. The goals of this paper are to presents a comprehensive review of the recent development in designing SAPV systems based on multi-objective optimization (MOO) and multi-criteria decision-making (MCDM) methodologies, including the mathematical models used in estimating the output power of the PV module and storage battery are also presented. Finally, the techno-economic criteria for assessing the performance of the SAPV system are considered. This will help the designers and customers to choose the most suitable design before installing the SAPV system. For supplementary resources and further discussions, please refer to the devoted homepage at http://aliasgharheidari.com .

Display Omitted Inflation rate increases material transferring entropy.Material transferring distortion cause creating dummy sub cells.Dummy sub cells decline system performance.A new method for measuring the system imbalance is proposed.A new method for minimizing system imbalance is proposed. Cell-load variation is considered as a major shortcoming in cellular manufacturing systems. It can cause long queues in front of machines and impose extra costs to the cellular layouts. In this paper the impact of inflation on cell-load variation in cellular manufacturing systems is examined. For this purpose, a new method is proposed for scheduling dynamic cellular manufacturing systems in the presence of bottleneck and parallel machines. The aim is finding the trade-off values between in-house manufacturing and using outsource services while system costs are not deterministic and may be varied from period to period by inflation. To solve the model, a hybrid genetic and simulated annealing algorithms is developed because of the high potential of outcomes to be trapped in the local optima. The results are then compared in LINGO 12.0 software. In continue a Taguchi method (an L9 orthogonal optimization) is used to estimate parameters of the proposed method in order to solve experiments derived from literature. Our findings show that the condition of dynamic costs affects the routing of materials in process and may induce machine-load variation that yield to cell-load diversity. An increase in changing costs causes the loading level of each cell to vary, which in turn results in the development of complex dummy sub-cells. To measure the level of cell-load variation a new mathematical index is developed. Then, a new method is proposed for minimizing cell-load variation in the mentioned condition by using control lines. The results indicate that the proposed method can significantly reduce the level of cell-load variation in CMS.

The power output delivered from a photovoltaic module highly depends on the amount of irradiance, which reaches the solar cells. Many factors determine the ideal output or optimum yield in a photovoltaic module. However, the environment is one of the contributing parameters which directly affect the photovoltaic performance. The authors review and evaluate key contributions to the understanding, performance effects, and mitigation of power loss due to soiling on a solar panel. Electrical characteristics of PV (Voltage and current) are discussed with respect to shading due to soiling. Shading due to soiling is divided in two categories, namely, soft shading such as air pollution, and hard shading which occurs when a solid such as accumulated dust blocks the sunlight. The result shows that soft shading affects the current provided by the PV module, but the voltage remains the same. In hard shading, the performance of the PV module depends on whether some cells are shaded or all cells of the PV module are shaded. If some cells are shaded, then as long as the unshaded cells receive solar irradiance, there will be some output although there will be a decrease in the voltage output of the PV module. This study also present a few cleaning method to prevent from dust accumulation on the surface of solar arrays.

Mechanisation of large-scale agricultural fields often requires the application of modern technologies such as mechanical power, automation, control and robotics. These technologies are generally associated with relatively well developed economies. The application of these technologies in some developing countries in Africa and Asia is limited by factors such as technology compatibility with the environment, availability of resources to facilitate the technology adoption, cost of technology purchase, government policies, adequacy of technology and appropriateness in addressing the needs of the population. As a result, many of the available resources have been used inadequately by farmers, who continue to rely mostly on conventional means of agricultural production, using traditional tools and equipment in most cases. This has led to low productivity and high cost of production among others. Therefore this paper attempts to evaluate the application of present day technology and its limitations to the advancement of large-scale mechanisation in developing countries of Africa and Asia. Particular emphasis is given to a general understanding of the various levels of mechanisation, present day technology, its management and application to large-scale agricultural fields. This review also focuses on/gives emphasis to future outlook that will enable a gradual, evolutionary and sustainable technological change. The study concludes that large-scale-agricultural farm mechanisation for sustainable food production in Africa and Asia must be anchored on a coherent strategy based on the actual needs and priorities of the large-scale farmers. © 2016 Society of Chemical Industry.

This paper presents a review of material transferring methods, related techniques, and their effects on cellular manufacturing systems (CMS). In-depth analysis has been conducted through a review of 95 dominant research papers available in the literature. The advantages, limitations, and drawbacks of material transferring methods have been discussed as well. The domains of the examined studies include some of the important problems in material transferring, such as exceptional elements, number of voids, machine distances, bottleneck machines and parts, machine location and relocation, part routing, cell load variation, inter and intracellular material transferring, cell reconfiguring, dynamic part demands, and operation and completion times. The results of this study can fill research gaps and clarify many related questions in CMS problems.

Lightning Surge protection of large structures is done under zonal concept due to the requirement of a system with high current handling capacity and low voltage protection level. Induction of transient voltage in the wiring system within the building is another reason for such. However, in the case of compact structures such as base transmission stations (BTS) of tower sites, outside broadcast vehicles (OBV), various stages of railway systems etc. there are no sufficient lengths in the wiring network for implementing SPDs in such zonal-segment scenario. Also due to the remoteness of most BTSs and need for regular and/or continuous usage of OBVs and railway systems, the time-consuming replacement of outof-order fixed SPDs is most often not warranted. In this backdrop, it was proposed to develop a portable/pluggable system of coordinated SPDs with high current handling capacity and low voltage protection level. A compact SPD system that is capable of handling high currents (50 kA) with low let through voltage (1 kV) was designed using PSCAD and a thorough market research was conducted to identify products that satisfied the requirements of the system designed in PSCAD. Type I and III SPDs capable of handling 50 kA and 2.5 kA respectively, were identified and used for the hardware implementation of the system. Elimination of the type II SPD made the design more compact and better suited for applications at space-restricted locations

In the event of a direct lightning strike to a protected building which is integrated with an electrical or electronic system installed on the roof such as roof-top PV system, dangerous arcing may occur between the external lightning protection system (LPS) and the conductive components of the electrical system. To prevent such side flashes, a minimum separation distance between the metallic components and the air termination system is required. Even though, IEC62305-3 Standard provides a formula to specify the necessary separation distance, so far there is no extensive study that has been done to evaluate the suitability of the application of equation to calculate the separation distance, specifically to the safety of electrical systems integrated into the roof top of building. In this study, a new computational method has been developed for calculation of the separation distance between an LPS and metallic components on the roof. In the proposed method which is based on the theoretical background of the IEC62305-3 Standard formula, the break down behavior of the gap geometry between the LPS and the metallic components for the applied voltage across the gap is analyzed. PSCAD software was used to model the LPS and the lightning strokes.

Plant diseases contribute to significant economic and post-harvest losses in agricultural production sector all over the world. Early detection of plant diseases and pathogens is crucial for maintaining the sustainability of the agricultural sector. In this regard, non-destructive techniques are one of the most practical and feasible ways of monitoring health conditions of plants for real-time applications. Current methods that involve molecular and serological methods are time-consuming, laborious, and require complex procedures. Hence, non-destructive methods are preferable since no sample preparation and repetitive processes are needed for the measurements. The prevention of plant disease and pathogens during the preliminary stage aids to the health control and yield optimisation without depending on the pest and pesticides usage. These techniques are boosted by the development of advanced technologies where computer-aided systems are employed for monitoring plant diseases. It is also vital to analyse the disease spread in plants for overcoming the issues related to physiological and biological states in crop protection. Most often a wide range of non-destructive techniques is needed to provide rapid detection of plant infections even in the case of one plant type. This study reviews the applications of non-destructive techniques including image processing, imaging-based, spectroscopy-based and remote sensing methods in monitoring and detecting plant diseases. The non-invasive techniques have also been investigated for their fundamental concepts and potential applications in developing sensing devices for fieldwork.

Agriculture is a main source of income, employment, and livelihood of a significant proportion of the populations of developing countries. Agricultural mechanization has now been in progress for several decades. However, it has been mainly confined to developed countries and a small number of developing countries. Some of the developing nations have had little or no progress in this area of agriculture production until recent times. Particularly, in sub-Saharan Africa, where 65% of agriculture is still carried out by manual labor, 25% by animal traction, and only 10% is mechanized (Esdaile, 2016). This is compared with the rapidly improved situation in countries like China,Sri Lanka, and Cambodia. Mechanization of agricultural production requires the applications of modern technologies. These technologies, however, are generally associated with relatively well-developed economies or largescale farms. The application of these technologies in many developing countries in Africa, Asia, and Latin America are limited by factors such as the technology’s compatibility with the environment, availability of resources to facilitate the technology’s adoption, cost of the technology, government policies, adequacy of the technology, and appropriateness in addressing the needs of the population. As a result, many of the available resources have been inadequately used by farmers. This has led to low productivity and high cost of production.

Dumps of a mining-metallurgical complex of post-Soviet Republics have accumulated a huge amount of technogenic waste products. Out of them, Kazakhstan alone has preserved about 20 billion tons. In the field of technogenic waste treatment, there is still no technical solution that leads it to be a profitable process. Recent global trends prompted scientists to focus on developing energy-saving and a highly efficient melting unit that can significantly reduce specific fuel consumption. This paper reports, the development of a new technological method-smelt layer of inversion phase. The introducing method is characterized by a combination of ideal stirring and ideal displacement regimes. Using the method of affine modelling, recalculation of pilot plant's test results on industrial sample has been obtained. Experiments show that in comparison with bubbling and boiling layers of smelt, the degree of zinc recovery increases in the layer of inversion phase. That indicates the reduction of the possibility of new formation of zinc silicates and ferrites from recombined molecules of ZnO, SiO2, and Fe2O3. Calculations show that in industrial samples of the pilot plant, the consumption of natural gas has reduced approximately by two times in comparison with fuming-furnace. The specific fuel consumption has reduced by approximately four times in comparison with Waelz-kiln.

This paper presents an intelligent fault location technique for the radial unbalanced distribution systems, based on the meseurments of Short Circuit Power (S/C.P) values at the primary bus. A Multi-Layer Feed ForwardNeural Network (ML-FFNN) with the tunned parameters is designed to evaluate the measurments. The estimated locations of different fault types are compared with the actual distances and Difference Percentage is calculated for each location. To examine the performance of the proposed technique in presence of DG units, the senario is also repeated including a DG unit in the simulated distribution network and the acuired result are presented. The proposed fault location technique is capable of being implemented with the small scale dataset which is applicable for the real distribution networks.

The behaviour of a lightning current traversing along a tall structure is influenced by the factor of the ground reflection coefficient parameter. This parameter is widely assumed to be constant in the analysis of lightning current along at all structure. However, in reality, the ground reflection depends on the relationship between the tower and ground impedances which results in multiple values for the ground reflection coefficient. These values are determined by the ground impedance, whereby the grounding electrode arrangement and soil resistivity play key roles. Hence, this study evaluates the effect of the grounding system on the lightning current profile along a tall structure. The lightning current along a tall structure is simulated by the implementation of a distributed source representation model. The results indicate that a multiple ground reflection coefficient is generated for different types of grounding electrode arrangements and soil resistivity values. The grounding electrode arrangement in horizontal, grid or circular forms provides at least a reduction of 30% reflected current along a tall structure for a high soil resistivity. Hence, this result may provide a general guide for telecommunication (TM) engineers to consider the condition of soil resistivity and the grounding system before installing a TM tower.

This paper is to study the effect of electric field on an angle variation of copper down-conductor due to voltage and current transient. Down-conductor which informs of numerous material, shape and dimension are mandatory for diverting the lightning current from air termination system to the grounding system in sheltered building. Hence, a numerical analysis method is applied emulating the comprehensible and particular model according to ordinarily used in the manufacturer’s datasheet specification. A rigorous assessment in term of electric fields was reviewed in comparison with the critical breakdown value of air for a crucial study. Later, a foremost angle is proposed for the installation of down-conductor in order to achieve a reliable protection system.

The evaluation of the behaviour of lightning current along a tall structure is becoming an important issue when considering the lightning protection equipment required along a tall structure. This behaviour is affected by the element of the ground reflection factor which has a correlation between the impedance of the ground and the tower. The impedance of the ground is considered for a horizontal grounding arrangement while the impedance of the tower is assumed to be constant. Hence, the ground reflection factor can be given a variable value, whereas most of the existing literature assumes a constant value. When a constant value is entered into a calculation field, an inaccurate result is computed.In this paper, the lightning current along a tall structure under varying values of ground reflection factor and including the effect of the presence of a horizontal grounding arrangement has been considered and the results discussed accordingly. Modelling of the lightning return stroke current along a tall structure was undertaken by entering the calculated variable value of the ground reflection factor. The results indicated that a variable value of the ground reflection factor causes different peak values of the current and wave shape of the lightning current for different positions along a tall structure.

High power microwave systems have emerged as a promising new technology that has many applications, which include high power radar, directed energy weapons, laboratory sources for susceptibility and vulnerability testing of electronic systems. These systems are built, applied, and studied in many developed countries such as in United States of America and China. In the recent years, other countries such as Russia, Western Europe, Japan, Taiwan, India, South Korea, and Singapore have also entered the research spheres. In this paper an introduction to the emergence of HPM and the sequential evolution of the technology, that plays an important role in several applications, are discussed. The discussion extends to types of HPM sources, and their effects of electromagnetic interference on electronic systems.

The 2005 earthquake in Pakistan engraved one of the worst natural hazards in the history of mankind. The mass destruction caused by nature in several parts of Azad Jammu Kashmir is revisited to assess the public impact. Several visits were paid to the most affected areas of the region, especially Muzaffarabad, to collect data on debris flow patterns, loss of vegetation, instability of the surface structure and buildings, impacts on social structure etc. Influences of pre-slide activities, both natural and man-made, on the pattern of landslides and triggering factors were investigated. The major landslide catastrophe that took place in Attabad in January 2010 was discussed as a case study. Attempts were made to correlate observations elsewhere with collected data, pertinent to 2005 earthquake in Pakistan with the objective of proposing safety guidelines to prevent or at least minimize such human catastrophes in the future, in the case of such an event.

Protection of medium voltage (MV) overhead lines against the indirect effects of lightning is an important issue in Malaysia and other tropical countries. Protection of these lines against the indirect effects of lightning is a major concern and can be improved by several ways. The choice of insulator to be used for instance, between the glass, ceramic or polymer, can help to improve the line performance from the perspective of increasing the breakdown strength. In this paper, the electrical performance of a 10 kV polymer insulator under different conditions for impulse, weather and insulator angle with respect to a cross-arm were studied (both experimental and modelling) and the results were discussed accordingly. Results show that the weather and insulator angle (with respect to the cross-arm) are surprisingly influenced the values of breakdown voltage and leakage current for both negative and positive impulses. Therefore, in order to select a proper protection system for MV lines against lightning induced voltage, consideration of the local information concerning the weather and also the insulator angles with respect to the cross-arm are very useful for line stability and performance.

Medical imaging techniques have widely been in use in the diagnosis and detection of breast cancer. The drawback of applying these techniques is the large time consumption in the manual diagnosis of each image pattern by a professional radiologist. Automated classifiers could substantially upgrade the diagnosis process, in terms of both accuracy and time requirement by distinguishing benign and malignant patterns automatically. Neural network (NN) plays an important role in this respect, especially in the application of breast cancer detection. Despite the large number of publications that describe the utilization of NN in various medical techniques, only a few reviews are available that guide the development of these algorithms to enhance the detection techniques with respect to specificity and sensitivity. The purpose of this review is to analyze the contents of recently published literature with special attention to techniques and states of the art of NN in medical imaging. We discuss the usage of NN in four different medical imaging applications to show that NN is not restricted to few areas of medicine. Types of NN used, along with the various types of feeding data, have been reviewed. We also address hybrid NN adaptation in breast cancer detection.

The application of renewable energies has increased rapidly in the previous decade to solve some problems such as growing energy demand and environmental issues. Wave power as a high potential renewable energy, is more predictable compared to other renewable sources. Although there are many research works about wave energy, however a few of them considered a suitable wave energy converter (WEC) as a power system for remote islands. Wave energy potential for remote islands is discussed in this review by regarding environmental impacts, various types of wave energy converters and applied wave power projects for various islands. The results show that wave energy plays a key role for sustainable development of offshore islands by considering the traditional looks and environmental protection.

The industry of civil aviation is developing in a fast manner to occupy the increasing needs for a fast, safe and comfortable transportation. To achieve these needs, some effective programs, plans, and systems designs are required. The current reliable aircraft navigation and landing systems have relatively a low level of accuracy especially in aircraft landing stage. The best landing category could be achieved requires a runway visual range up to 50 meters and automatic landing system is not in operation yet all over the world. Aircraft navigates using Radar, Radio and Satellite navigation systems. The Federal Aviation Administration (FAA) plans to replace legacy navigation systems with satellite based navigation technology. Currently, the Global Positioning System (GPS) and its augmentations is the main satellite navigation system used all over the world for air navigation applications. The development of aircraft navigation has been performed with the enhancement of GPS augmentation systems. In this paper, aircraft navigation systems and techniques will be presented in this paper to evaluate the integrity and reliability of each system, and to make a comparison among these systems according to accuracy, integrity and availability.

Practical challenges of electrical earthing in both steady and transient states have been revisited. By analyzing the cases based on theoretical and practical aspects, engineering guidelines are proposed to develop suitable solutions. Less complicated cases can be approached with various electrode configurations such as multiple ring, antenna, crow-foot and centipede arrangements. Distributed earthing arrangements treated with backfill materials are suitable for the sites with extremely high resistive soil. Clay based backfill materials such as bentonite-mix give corrosion and erosion protection for the electrodes in highly acidic, alkaline, saline and sulfur-rich environments apart from reducing the low frequency resistance. On-rock sites such as transmission and communication towers are better approached with concrete-based earthing systems in both cases of power and lightning protection earthing. Extreme cases of soil instability have been identified and discussed. The suitability of vertical and horizontal electrode components as well as copper and steel electrodes under various soil conditions is also discoursed. For most cases, we recommend all types of earthing systems to be integrated, however, properly coordinated system of Surge Protective Devices (SPDs) should be incorporated in such integrated earthing system.

People are very vulnerable in case of natural disasters. Power grid destruction is a common disaster in these situations. Numerous costumers might easily lose access to electric power and this condition can continue for a long time after the catastrophe. Emergency shelter after occurrence of disasters is usually offered by organizations or governmental emergency administration departments, as a comeback to natural disasters, such as an earthquake or flood. They tend to use tents or other temporary structures, or buildings. This paper focus on design of a Smart Hybrid power supply for shelter which is supported from three renewable energy source (wind, rain and solar) that is available in each condition in order to be used during emergency situation as a portable facility by analyzing the power generation ability and also the load demand characteristics during natural disaster for relief shelters.

International Standards on lightning protection risk assessment (IEC 62305-2: 2010) are well accepted and applied in many parts of the world. During the last few years a large number of lightning related accidents, especially due to direct strikes, have been reported from Asia and Africa where the lightning struck objects are small structures. Information gathered from several investigations done on these cases have been used to determine the level of protection needed for these structures as per the standard risk assessment. In many cases the outcome was the none-requirement of any LPS for such structures or a risk factor for direct strike probability which is less than the critical value. As there are millions of similar structures in these regions, we propose the development of a separate risk assessment algorithm for such structures, especially in underdeveloped countries.

How is lightning protection ranked in the field of safety science? What is the general perception of the public with regard to the risk of receiving a lightning strike to their building? How do business entities manipulate the psyche of the public in upsizing financial gains? What is the true risk of public adopting lightning protection techniques that have not been included in major international standards? Is the research presented so far in condemning the lightning protection systems rejected by the scientific community, well-conducted? Is tabooing of some lightning protection technologies a productive strategy in driving the public to adopt protection systems recommended by international (IEC) standards? This paper makes comprehensive attempts to answer these questions.

When a tower is struck by lightning, an induced voltage can generate in conducting objects within its vicinity. This phenomenon is due to the interaction between the electromagnetic field of the lightning with the object. The magnetic field is part of this field. Previous studies have shown that the magnetic field is affected by ground reflection coefficient factors that are usually taken as constants. However, the ground reflection coefficient factors have correlation with tower and ground impedance whereby the ground impedance can be determined based on soil resistivity and grounding system. This paper investigates the effect of soil resistivity on the value of magnetic field for a case of lightning strike on tall structures. Lightning current has been modelled accordingly and a set of equations is proposed to evaluate the magnetic field. Also, the effects of soil resistivity on the value of ground reflection coefficient factor consequently of the magnetic peak have been investigated. The results indicate that the magnetic field changes substantially with a variation of the soil resistivity. The magnetic field peak also has a strong correlation with the changes of soil resistivity as well as the fast front time of the channel base current. The outcome of the result of this paper will be beneficial to utility companies in determining the appropriate level of lightning protection since the magnetic field will be a result of induced voltage when have interaction with power lines.

This paper validates the performance of low-cost lightning protection systems for small structures proposed by researchers in the past. Such structures have an acute demand in the countries with very high lightning ground flash density, yet the affordability of the mass public is quite limited due to the struggling economies of the countries. The protection systems for small housing structure, and a standalone protection structure for one or few people have been investigated by implementing the structures in HFSS/ANSYS software which employs finite element method. By applying current waveforms to represent first negative return stroke, subsequent negative return stroke and positive return stroke, the electric field and potential gradient of the entire space and the current density and the thermal profile of the protective structure have been computed. The objectives were to find whether the voltage distribution in the wake of a lightning strike could initiate side flashes, generate touch potential and step potentials that exceed dangerous levels, drive current densities due to which the structure collapse under thermal effects. It has been found that the proposed protective structures could suppress side flashes and harmful effects due to step potential while the structure will be able to withstand the heat generated. However, the touch potential could still be beyond the human injury thresholds, thus a minimum separation from the lightning current passage should be advised to the occupants.

A direct lightning strike to a tall structure can impart high impact damage to electrical equipment that may be installed within and around the structure. This is due to the behaviour of the lightning return stroke current which generates a lightning electromagnetic field (LEMF) and consequently creates an induced voltage (LIV) on the electrical equipment. The lightning return stroke current along the channel is influenced by the parameters of the return stroke velocity (RSV). The return stroke velocity can be determined by measurement. Mostly, this value is considered as the average value in the range c/2 to 2c/3 for the first hundred metres of channel height, which should be taken into account when calculating the LEMF. Hence, the result of the evaluation of lightning return stroke current behaviour will inherently influence the evaluation of the lightning protection that is required for the electrical equipment surrounding the tall structure. However, when performing measurements, the return stroke velocity shows a changing trend value for different channel heights. In this paper, this trend will be used to evaluate the return stroke current at different heights along a channel. Thus, modelling of a lightning current along a channel was undertaken. Also, the return stroke velocity for different channel heights was calculated by considering the initial delay time. The results indicate that the lightning current along the channel has a significant effect on the changes in the return stroke velocity profile.

This study analyzed and compared the lightning related casualties in Malaysia and United States. United States as a developed country is reported with 0.3 deaths per million per year after 1970 comparing to lesser-developed areas such as Malaysia with an annual lightning fatality rate of 6 deaths per million. The comparison and analysis were made based on the rural-urban setting and the six types of activities locations defined as agriculture, indoors, outdoors, recreation, small structures (i.e. vehicle, open-sided shelter, shed) and sports. The results for the both countries were discussed in terms of their differences and similarities.

Lightning induced voltage is one of the important issues pertinent to line interruptions in distribution lines. The behaviour of a polymer insulator under different weather conditions may affect the overall stability of a power flow in the line. In this paper, the lightning induced voltage due to a typical sample of return stroke current on a distribution line has been investigated, and the electrical behaviour of a polymer insulator (10 kV) under different air humidity conditions was analysed in detail. The results show that the air humidity has a direct effect on the electrical performance of a polymer insulator under lightning induced voltage conditions, which reduces the reliability of the system. Therefore, in designing new distribution lines and in modifying existing lines, various safety and protection parameters such as determining the critical distances around the distribution lines where lightning induced over voltage (LIOV) may occur, the humidity of air should be treated as an essential input parameter. Thus, the field propagation along an insulator based on recorded local information (weather conditions) can be helpful and should be taken into account in taking protection measures.

This paper provides an insight to the feasibility of adopting hydrogen as a key energy carrier and fuel source in the near future. It is shown that hydrogen has several advantages, as well as few drawbacks in using for the above purposes. The research shows that hydrogen will be a key player in storing energy that is wasted at generation stage in large-scale power grids by off-peak diversion to dummy loads. The estimations show that by the year of 2050 there will be a hydrogen demand of over 42 million metric tons or 45 billion gallon gasoline equivalent (GGE) in the United States of America alone which can fuel up 342 million light-duty vehicles for 51 × 1011 miles (82 × 1011 km) travel per year. The production at distributed level has also been discussed. The paper also presents the levels of risk in production, storage and distribution stages and proposes possible techniques to address safety issues. It is shown that the storage in small to medium scale containers is much economical compared to doing the same at large-scale containers. The study concludes that hydrogen has a promising future to be a highly feasible energy carrier and energy source itself at consumer level.